The next series of analyses will compare the differences in vitamin D between supplemented groups over time between ethnic groups. This will be accomplished by use of a two-way (ethnicity and supplementation group) repeated measures analysis of variance. This technique will detect any significant differences between main effects (ethnic groups and supplementation groups) and interaction effects (ethnicity by supplementation) in changes in vitamin D over time. Multiple regression also will be used to examine the changes with and without the use of potential confounders.